Question

Choose the correct order of steps for the synthesis of Vitamin D.

a. Inactive vitamin D is transported to the liver where it is modified.
b. Inactive, chemically altered vitamin D is transported to the kidneys.
c. UV light strikes the skin and converts a steroid molecule into an inactive form of vitamin D.
d. Vitamin D is activated under the influence of PTH.


A. d, a, c, b
B. a,c,b,d
C. a, b, c, d
D. c, a, b, d
E. c, b, a, d

Answer 1

Answer:D. c, a, b, d

Explanation:humans can synthesis vitamin D as cholecalciferol in the skin when the skin is exposed to ultraviolet-B from the sun.this cholecalciferol is modified to calcidiol in the liver.this calcidiol is then modified to calcitrol in the kidney.parathyroid hormone activates the vit D